Description: Vitreous hemorrhages diminish vision, may mask retinal detachments and predispose for proliferative vitreoretinopathy. One current treatment removes all or part of the vitreous (vitrectomy) but can be associated wit complications. Clearly, the development of a simple, non-surgical procedure for vitreous hemorrhage would be extremely beneficial. The PI has patented a drug suitable for intravitreal injection which increases the clearance rate of intravitreal blood. FDA approved Phase I safety trials are scheduled to begin. The PI proposes concurrent animal studies. The specific aims are to determine the: 1). Duration of the drug in the vitreous. 2). Changes in the extracellular matrix after drug application. 3). Effects of the drug upon endogenous enzymes. 4). Changes in the retina after drug application. 5). Long term effect of blood and the drug on the retina. The objective is to demonstrate that this drug is a safe, effective alternative to vitrectomy after vitreal hemorrhage. Patient benefits are improved vision, earlier diagnosis and treatment, and decreased risks. As some 640,000 vitreal hemorrhages and 100,000 vitrectomies occur annually, this non-surgical protocol has great clinical and economic significance. PROPOSED COMMERCIAL APPLICATION: This product would be an alternative to surgery and could be used to ameliorate the adverse visual consequences of retinal hemorrhages. This procedure, if proven to be safe and effective, could be lower the cost of care for patients who develop visual problems related to this pathology.